Official Luthiers Forum!

Besides 3M Scotch Weld, what have you all found that works well for bonding wood to metal--preferably an adhesive that's sold in a small amount. I need to glue several strips of .020 X 3/8" X 4" steel to wood.
Thanks in advance.

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michael propsom
www.propsomguitars.com

Most epoxies would work, I'd avoid the 5 min type though.Give your metal a scuffing with sand paper or scotch brite and give it a good cleaning and you should be fine.

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Jim Watts
http://jameswattsguitars.com

I'm thinking about making a guitar with aluminum binding for my friend Shaun Hopper. He does this percussion thing that's wearing a hole in the side of his guitar.

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Old growth, shmold growth!

With aluminum if you don't bond right after sanding you'll end up bonding to an oxide layer at about 1/3rd the strength than if you treat it right. PM me and I'll go over it all with you.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Words of wisdom there.

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Jim Watts
http://jameswattsguitars.com

What about 10 min? That's all I found around and I need to glue lignum vitae scales to a fancy hunting knife I'm making for a friend

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Build log

I found the only way to reliably bond metal to wood is either epoxy or mechanical fasteners.

Problem with aluminum is the oxide layer forms within seconds of being sanded or scratched, so its impossible to have aluminum completely free of oxide layers in normal atmosphere. That's why welding or soldering aluminum is so difficult.

Steel isn't so bad, epoxy will bond but if you're using something like system three make sure you thicken the epoxy first or else the wood will suck away all the epoxy and make the bond weak. In this case it is better to use epoxy adhesives rather than ones for fiberglass.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Marine Tex

I would rethink metal as a binding. Binding is there as a protective against bumps and dings. Metal like aluminum is very soft and will not protect the guitar. You also have a shrinkage and contraction issue and a safety concern .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I used slow set epoxy on a slab git with copper bindings,
and it's held up for about 17 years.

I wouldn't count on any glue for the application you describe. Lignum Vitae is famously hard to glue. Any wood-steel glue joint will have to deal with severe shear stresses. (You'll note that most knife scales are mechanically joined.) If you are determined to try glue, you'll want a high strength, industrial epoxy, not any of the hardware store options. De-wax the wood with multiple acetone baths, and sand-blast the steel. When the bond fails, go back to a riveted joint.

When I made handles for violin knives, I glue them together with the knife inside so that the wood itself wedges the knife in itself. So its the wood to wood bond holding it together rather than wood to metal.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I would have used a mechanical male/female assembly but after not finding the suited size and reading around it seems that many custom knifes these days are made with epoxy rather than the old fashioned way. The pins are simply press-fitted into the holes and epoxied too, not riveted.

Lignum vitae is indeed special. Planing it makes the sole feels like it has been generously waxed. The wood in itself feels waxed. Even so, I did some tests with fish glue (no acetone/alcohol) and it holds reasonably well. I still got some wood failure when trying lignum with mahogany and spruce. In any case I will do a test with steel and acetone cleaned lignum scraps before.

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Build log

You might want to read up on the history of epoxy bonding in the aircraft industry circa 1960-1980 (When Boeing nearly went bankrupt because of glue failures). Telephones have come a long way--guitars, knives, epoxy, not so much.

For the wood, do the standard procedure: clean, fresh surface. Doesn't matter much if you sand it or plane it that way, but if you sand it then you need to blow compressed air on it until every last little speck of sanding dust is actually gone.

For the metal the process is a bit more complicated. Clean it with acetone three times, etch it, flame or corona treat it, wipe once more with acetone and then glue as quickly as you can. Use a new, clean rag for each acetone cleaning. Kimwipes or at least a brand new roll of 'shop towels' blue paper towel are recommended. As others have, I'd recommend epoxy as the easiest to pull this off with although CA will work in ideal conditions.

I have less experience with steel, but the standards for etching it are strong acids, sulfuric or nitric, or things that make strong acids in water (Ferric Chloride, used in PCB etching). Etch aluminum with a strong base (counter-intuitive, at least to me) as this removes the oxide layer and cooks into the surface pretty well.

The more steps you skip in there, the weaker the bond will be. You can get a nice strong bond to metal, but the prep is killer. Check this out:

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

I was going to use a 3/16" x 0.5mm copper filament for the binding. I have decided it would be best to use it as an outside layer on a multi layered binding. My thinking was along the same lines as Bob Garrish; clean it well then an acid bath of sulfuric acid, clean again then use epoxy for the adhesive. This thread gave me a little more confidence that I was on the correct train of thought. I think the copper would look good on the Black Walnut.

Thanks,

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Joe

My wife asks me "How many Guitars do you need?"
I reply "When I die count them; thats how many I needed".

Carriage bolts work well.

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Freeborn Guitars
and home of BeauGuard©

I would think something along the lines of how fret wire anchors would help--with barbed tangs of some sort--but that's not easy maybe. Or could it be done?

Just a thought.

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

Polyurethane or weldbond works well.